Smallest member of the Procellaria. No subspecies
recognized. New Zealand Maori name is 'Taiko', not to be confused with
the Chatham Island Taiko or Magenta Petrel.
Difficult! A medium-sized, stocky, uniformly dark petrel that is very similar to both Westland Petrel and White-chinned Petrel. According to Palliser (1999), easily overlooked among Flesh-footed Shearwaters. However, Black Petrels appear slightly bulkier and more bull-headed than Flesh-footed Shearwater. Swims well and will dive for sinking food (up to 10 m below the surface). Flight said to be less laboured than Westland or White-chinned Petrels but this subjective criteria is likely to be of limited use in a field situation. Can soar and arch in an albatross fashion in high winds. In fresh plumage, paler undersides of the primariers contrast with darker, less reflective underwing coverts. With wear, the entire plumage becomes browner.
Careful examination of the bill is critical, although
this can be variable in terms of shape and length. Both Black and Westland
Petrels differ from White-chinned Petrel in having a dark tip to the bill.
Separation between the two is more tricky and the features to be looked
for include the extent of the dusky tip and the height of the maxillary
unguis compared to the height of the culminicorn. Bill plates are yellowish
horn, although this looks white at a distance. For a fantastically detailed
view of the bill, check out this head
shot from Tony Palliser's web site.
Where and When
Breeding now restricted to ridge-top forests on the highest parts of Great (c. 800 pairs) and Little Barrier Islands (c. 100 pairs) in the Gulf of Hauraki in northern New Zealand. Once nested in the more extensive forests of the main islands (south to Heaphy Range near Nelson on the North Island and southeastern parts of the South Island) and presumably was once more abundant. May have overlapped with Westland Petrel. Unlike the closely-related Westland Petrel, Black Petrel breeds during the austral summer (Nov-July). Eggs layed in late November and December. Total world population estimated at only 3000-4000 individuals. Breeding birds feed in sub-tropical waters around the North Island of New Zealand and further eastwards (30-42 deg. S). Especially common in seas around breeding islands, and may form large flocks (e.g 300 birds) near feeding cetaceans. Also ranges into the Tasman Sea and eastern Australia.
Outside the breeding season (ie. Mar-Nov), disperses
into the eastern tropical Pacific reaching Mexico, Central America, The
Galapagos, Ecuador and Peru. A few non-breeders may remain all year. Attends
trawlers and is vulnerable to fatalities in longline fishing. Feed predominantly
on squid, supplemented with fish and crustaceans. High fraction of bioluminescent
squid in diet suggests much feeding is done at night.
Photographs on the web
in flight Astoundingly clear picture from Tony Palliser's collection.
On waterfrom Tony Palliser's collection.
Tony Palliser (1999) [BIRDWG01] 'black' Procellaria petrels. Posting to NBHC Id-Frontiers on 28 Jan 1999.
Pitman, R.L. and L.T. Ballance. (1992) Parkinson's
Petrel distribution and foraging ecology in the eastern tropical Pacific:
aspects of an exclusive feeding relationship with dolphins. Condor, 94: